This application relates to knife edge seals which rotate with a gas turbine rotor, and are associated with concave pockets in a stationary sealing surface. The combination of the knife edge seals and the concave pockets create vortices, which limit leakage past the knife edge seals.
Gas turbine engines are known, and typically include a series of sections. Generally, a fan delivers air to a compressor section. Air is compressed in the compressor section, and delivered downstream to a combustor section. In the combustor section, air and fuel are combusted. The products of combustion then pass downstream over turbine rotors. The turbine rotors rotate to create power, and also to drive the fan and compressors.
The turbine rotors typically are provided with a plurality of removable blades. The blades are interspersed with stationary surfaces, and stationary vanes. It is desirable to limit leakage of the products of combustion radially inwardly of the turbine blades. Thus, the turbine blades are provided with knife edge seals which are spaced closely from sealing surfaces on the static members.
In the prior art, labyrinth seal structures are known. Generally, the sealing surfaces have been formed as cylindrical surfaces at a plurality of different radial distances. The combination of these different radial distances, and a plurality of associated knife edge blades create a labyrinth path for leakage fluid to limit it reaching radially inner locations in the gas turbine engine. Even so, some leakage does occur, and it would be desirable to further reduce the leakage.